*: generously apply const

const const const your boat, merrily down the stream...

Signed-off-by: David Lamparter <equinox@diac24.net>

64 files changed, 194 insertions, 174 deletions

diff --git a/babeld/babel_main.c b/babeld/babel_main.c
index bb3378f4f..6f4b905c1 100644
--- a/babeld/babel_main.c
+++ b/babeld/babel_main.c
@@ -74,7 +74,7 @@ unsigned char protocol_group[16]; /* babel's link-local multicast address */
 int protocol_port;                /* babel's port */
 int protocol_socket = -1;         /* socket: communicate with others babeld */
 
-static char babel_config_default[] = SYSCONFDIR BABEL_DEFAULT_CONFIG;
+static const char babel_config_default[] = SYSCONFDIR BABEL_DEFAULT_CONFIG;
 static char *babel_vty_addr = NULL;
 static int babel_vty_port = BABEL_VTY_PORT;
 
diff --git a/babeld/babel_zebra.c b/babeld/babel_zebra.c
index 5a336df7b..86f8bc721 100644
--- a/babeld/babel_zebra.c
+++ b/babeld/babel_zebra.c
@@ -39,7 +39,7 @@ void babelz_zebra_init(void);
 struct zclient *zclient;
 
 /* Debug types */
-static struct {
+static const struct {
     int type;
     int str_min_len;
     const char *str;
diff --git a/bfdd/bfd.h b/bfdd/bfd.h
index eddfde62f..ac413cafc 100644
--- a/bfdd/bfd.h
+++ b/bfdd/bfd.h
@@ -399,8 +399,8 @@ struct bfd_global {
 	struct zebra_privs_t bfdd_privs;
 };
 extern struct bfd_global bglobal;
-extern struct bfd_diag_str_list diag_list[];
-extern struct bfd_state_str_list state_list[];
+extern const struct bfd_diag_str_list diag_list[];
+extern const struct bfd_state_str_list state_list[];
 
 void socket_close(int *s);
 
diff --git a/bfdd/bfdd.c b/bfdd/bfdd.c
index a9528646d..341edbe5c 100644
--- a/bfdd/bfdd.c
+++ b/bfdd/bfdd.c
@@ -122,7 +122,7 @@ FRR_DAEMON_INFO(bfdd, BFD, .vty_port = 2617,
 		.n_yang_modules = array_size(bfdd_yang_modules))
 
 #define OPTION_CTLSOCK 1001
-static struct option longopts[] = {
+static const struct option longopts[] = {
 	{"bfdctl", required_argument, NULL, OPTION_CTLSOCK},
 	{0}
 };
@@ -133,7 +133,7 @@ static struct option longopts[] = {
  */
 struct bfd_global bglobal;
 
-struct bfd_diag_str_list diag_list[] = {
+const struct bfd_diag_str_list diag_list[] = {
 	{.str = "control-expired", .type = BD_CONTROL_EXPIRED},
 	{.str = "echo-failed", .type = BD_ECHO_FAILED},
 	{.str = "neighbor-down", .type = BD_NEIGHBOR_DOWN},
@@ -145,7 +145,7 @@ struct bfd_diag_str_list diag_list[] = {
 	{.str = NULL},
 };
 
-struct bfd_state_str_list state_list[] = {
+const struct bfd_state_str_list state_list[] = {
 	{.str = "admin-down", .type = PTM_BFD_ADM_DOWN},
 	{.str = "down", .type = PTM_BFD_DOWN},
 	{.str = "init", .type = PTM_BFD_INIT},
diff --git a/bgpd/bgp_addpath.c b/bgpd/bgp_addpath.c
index cf51960b7..e7e7c3cc1 100644
--- a/bgpd/bgp_addpath.c
+++ b/bgpd/bgp_addpath.c
@@ -24,7 +24,7 @@
 #include "bgp_addpath.h"
 #include "bgp_route.h"
 
-static struct bgp_addpath_strategy_names strat_names[BGP_ADDPATH_MAX] = {
+static const struct bgp_addpath_strategy_names strat_names[BGP_ADDPATH_MAX] = {
 	{
 		.config_name = "addpath-tx-all-paths",
 		.human_name = "All",
@@ -41,7 +41,7 @@ static struct bgp_addpath_strategy_names strat_names[BGP_ADDPATH_MAX] = {
 	}
 };
 
-static struct bgp_addpath_strategy_names unknown_names = {
+static const struct bgp_addpath_strategy_names unknown_names = {
 	.config_name = "addpath-tx-unknown",
 	.human_name = "Unknown-Addpath-Strategy",
 	.human_description = "Unknown Addpath Strategy",
@@ -53,7 +53,7 @@ static struct bgp_addpath_strategy_names unknown_names = {
  * Returns a structure full of strings associated with an addpath type. Will
  * never return null.
  */
-struct bgp_addpath_strategy_names *
+const struct bgp_addpath_strategy_names *
 bgp_addpath_names(enum bgp_addpath_strat strat)
 {
 	if (strat < BGP_ADDPATH_MAX)
diff --git a/bgpd/bgp_addpath.h b/bgpd/bgp_addpath.h
index c0c182791..786873a00 100644
--- a/bgpd/bgp_addpath.h
+++ b/bgpd/bgp_addpath.h
@@ -48,7 +48,7 @@ int bgp_addpath_info_has_ids(struct bgp_addpath_info_data *d);
 uint32_t bgp_addpath_id_for_peer(struct peer *peer, afi_t afi, safi_t safi,
 				struct bgp_addpath_info_data *d);
 
-struct bgp_addpath_strategy_names *
+const struct bgp_addpath_strategy_names *
 bgp_addpath_names(enum bgp_addpath_strat strat);
 
 int bgp_addpath_dmed_required(int strategy);
diff --git a/bgpd/bgp_aspath.c b/bgpd/bgp_aspath.c
index 4257b601f..5fa773c95 100644
--- a/bgpd/bgp_aspath.c
+++ b/bgpd/bgp_aspath.c
@@ -102,8 +102,10 @@ static void assegment_data_free(as_t *asdata)
 	XFREE(MTYPE_AS_SEG_DATA, asdata);
 }
 
-const char *aspath_segment_type_str[] = {"as-invalid", "as-set", "as-sequence",
-					 "as-confed-sequence", "as-confed-set"};
+const char *const aspath_segment_type_str[] = {
+	"as-invalid", "as-set", "as-sequence", "as-confed-sequence",
+	"as-confed-set"
+};
 
 /* Get a new segment. Note that 0 is an allowed length,
  * and will result in a segment with no allocated data segment.
diff --git a/bgpd/bgp_debug.c b/bgpd/bgp_debug.c
index 0e4c3a3e1..f716c4f30 100644
--- a/bgpd/bgp_debug.c
+++ b/bgpd/bgp_debug.c
@@ -101,7 +101,7 @@ const struct message bgp_status_msg[] = {{Idle, "Idle"},
 					 {0}};
 
 /* BGP message type string. */
-const char *bgp_type_str[] = {NULL,	   "OPEN",      "UPDATE",
+const char *const bgp_type_str[] = {NULL,	   "OPEN",      "UPDATE",
 			      "NOTIFICATION", "KEEPALIVE", "ROUTE-REFRESH",
 			      "CAPABILITY"};
 
@@ -169,8 +169,8 @@ static const struct message bgp_notify_capability_msg[] = {
 	{0}};
 
 /* Origin strings. */
-const char *bgp_origin_str[] = {"i", "e", "?"};
-const char *bgp_origin_long_str[] = {"IGP", "EGP", "incomplete"};
+const char *const bgp_origin_str[] = {"i", "e", "?"};
+const char *const bgp_origin_long_str[] = {"IGP", "EGP", "incomplete"};
 
 static int bgp_debug_print_evpn_prefix(struct vty *vty, const char *desc,
 				       struct prefix *p);
diff --git a/bgpd/bgp_debug.h b/bgpd/bgp_debug.h
index e05da3764..e1072c3df 100644
--- a/bgpd/bgp_debug.h
+++ b/bgpd/bgp_debug.h
@@ -151,8 +151,7 @@ struct bgp_debug_filter {
 #define BGP_DEBUG(a, b)		(term_bgp_debug_ ## a & BGP_DEBUG_ ## b)
 #define CONF_BGP_DEBUG(a, b)    (conf_bgp_debug_ ## a & BGP_DEBUG_ ## b)
 
-extern const char *bgp_type_str[];
-extern const char *pmsi_tnltype_str[];
+extern const char *const bgp_type_str[];
 
 extern int bgp_dump_attr(struct attr *, char *, size_t);
 extern int bgp_debug_peer_updout_enabled(char *host);
diff --git a/bgpd/bgp_fsm.c b/bgpd/bgp_fsm.c
index 1e5883814..6460ff76f 100644
--- a/bgpd/bgp_fsm.c
+++ b/bgpd/bgp_fsm.c
@@ -62,7 +62,7 @@ DEFINE_HOOK(peer_status_changed, (struct peer * peer), (peer))
 /* Definition of display strings corresponding to FSM events. This should be
  * kept consistent with the events defined in bgpd.h
  */
-static const char *bgp_event_str[] = {
+static const char *const bgp_event_str[] = {
 	NULL,
 	"BGP_Start",
 	"BGP_Stop",
@@ -522,7 +522,7 @@ int bgp_routeadv_timer(struct thread *thread)
 }
 
 /* BGP Peer Down Cause */
-const char *peer_down_str[] = {"",
+const char *const peer_down_str[] = {"",
 			       "Router ID changed",
 			       "Remote AS changed",
 			       "Local AS change",
diff --git a/bgpd/bgp_fsm.h b/bgpd/bgp_fsm.h
index 9d0500ae2..6f955c71b 100644
--- a/bgpd/bgp_fsm.h
+++ b/bgpd/bgp_fsm.h
@@ -64,7 +64,7 @@ extern int bgp_stop(struct peer *peer);
 extern void bgp_timer_set(struct peer *);
 extern int bgp_routeadv_timer(struct thread *);
 extern void bgp_fsm_change_status(struct peer *peer, int status);
-extern const char *peer_down_str[];
+extern const char *const peer_down_str[];
 extern void bgp_update_delay_end(struct bgp *);
 extern void bgp_maxmed_update(struct bgp *);
 extern int bgp_maxmed_onstartup_configured(struct bgp *);
diff --git a/bgpd/bgp_io.c b/bgpd/bgp_io.c
index 9e1c89b71..fed34e5b6 100644
--- a/bgpd/bgp_io.c
+++ b/bgpd/bgp_io.c
@@ -508,7 +508,7 @@ static bool validate_header(struct peer *peer)
 	uint8_t type;
 	struct ringbuf *pkt = peer->ibuf_work;
 
-	static uint8_t m_correct[BGP_MARKER_SIZE] = {
+	static const uint8_t m_correct[BGP_MARKER_SIZE] = {
 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 	uint8_t m_rx[BGP_MARKER_SIZE] = {0x00};
diff --git a/bgpd/bgp_keepalives.c b/bgpd/bgp_keepalives.c
index 3a49e8bc0..3a5adae87 100644
--- a/bgpd/bgp_keepalives.c
+++ b/bgpd/bgp_keepalives.c
@@ -95,7 +95,7 @@ static void peer_process(struct hash_bucket *hb, void *arg)
 	static struct timeval ka = {0}; // peer->v_keepalive as a timeval
 	static struct timeval diff;     // ka - elapsed
 
-	static struct timeval tolerance = {0, 100000};
+	static const struct timeval tolerance = {0, 100000};
 
 	uint32_t v_ka = atomic_load_explicit(&pkat->peer->v_keepalive,
 					     memory_order_relaxed);
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index f1bd4c77d..3f4ddef9f 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -10600,7 +10600,7 @@ enum bgp_stats {
 	BGP_STATS_MAX,
 };
 
-static const char *table_stats_strs[] = {
+static const char *const table_stats_strs[] = {
 		[BGP_STATS_PREFIXES] = "Total Prefixes",
 		[BGP_STATS_TOTPLEN] = "Average prefix length",
 		[BGP_STATS_RIB] = "Total Advertisements",
@@ -10858,7 +10858,7 @@ enum bgp_pcounts {
 	PCOUNT_MAX,
 };
 
-static const char *pcount_strs[] = {
+static const char *const pcount_strs[] = {
 		[PCOUNT_ADJ_IN] = "Adj-in",
 		[PCOUNT_DAMPED] = "Damped",
 		[PCOUNT_REMOVED] = "Removed",
diff --git a/bgpd/rfapi/rfapi_vty.c b/bgpd/rfapi/rfapi_vty.c
index 4fa64075c..5ad822211 100644
--- a/bgpd/rfapi/rfapi_vty.c
+++ b/bgpd/rfapi/rfapi_vty.c
@@ -127,8 +127,8 @@ void rfapiRprefixApplyMask(struct rfapi_ip_prefix *rprefix)
 	int index;
 	int offset;
 
-	static uint8_t maskbit[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0,
-				    0xf8, 0xfc, 0xfe, 0xff};
+	static const uint8_t maskbit[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0,
+					  0xf8, 0xfc, 0xfe, 0xff};
 
 	switch (rprefix->prefix.addr_family) {
 	case AF_INET:
diff --git a/bgpd/rfapi/vnc_debug.c b/bgpd/rfapi/vnc_debug.c
index 7cac7ac7a..2c5e18832 100644
--- a/bgpd/rfapi/vnc_debug.c
+++ b/bgpd/rfapi/vnc_debug.c
@@ -38,7 +38,7 @@ struct vnc_debug {
 	const char *name;
 };
 
-struct vnc_debug vncdebug[] = {
+static const struct vnc_debug vncdebug[] = {
 	{VNC_DEBUG_RFAPI_QUERY, "rfapi-query"},
 	{VNC_DEBUG_IMPORT_BI_ATTACH, "import-bi-attach"},
 	{VNC_DEBUG_IMPORT_DEL_REMOTE, "import-del-remote"},
diff --git a/eigrpd/eigrp_fsm.c b/eigrpd/eigrp_fsm.c
index cc6d47f48..e43eca0e0 100644
--- a/eigrpd/eigrp_fsm.c
+++ b/eigrpd/eigrp_fsm.c
@@ -110,7 +110,7 @@ int eigrp_fsm_event_qact(struct eigrp_fsm_action_message *);
  * NSM[actual/starting state][occurred event].func
  * Functions are should be executed within separate thread.
  */
-struct {
+const struct {
 	int (*func)(struct eigrp_fsm_action_message *);
 } NSM[EIGRP_FSM_STATE_MAX][EIGRP_FSM_EVENT_MAX] = {
 	{
diff --git a/isisd/isis_bpf.c b/isisd/isis_bpf.c
index d6b85b2fa..e916a5088 100644
--- a/isisd/isis_bpf.c
+++ b/isisd/isis_bpf.c
@@ -65,10 +65,13 @@ uint8_t *readbuff = NULL;
  * ISO 10589 - 8.4.8
  */
 
-uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
-uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
-uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
-uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
+static const uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
+static const uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
+#if 0
+/* missing support for P2P-over-LAN / ES-IS on BSD */
+static const uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
+static const uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
+#endif
 
 static char sock_buff[8192];
 
diff --git a/isisd/isis_csm.c b/isisd/isis_csm.c
index 88676dd99..9202ed5a8 100644
--- a/isisd/isis_csm.c
+++ b/isisd/isis_csm.c
@@ -50,12 +50,12 @@
 
 extern struct isis *isis;
 
-static const char *csm_statestr[] = {"C_STATE_NA", "C_STATE_INIT",
+static const char *const csm_statestr[] = {"C_STATE_NA", "C_STATE_INIT",
 				     "C_STATE_CONF", "C_STATE_UP"};
 
 #define STATE2STR(S) csm_statestr[S]
 
-static const char *csm_eventstr[] = {
+static const char *const csm_eventstr[] = {
 	"NO_STATE",     "ISIS_ENABLE",    "IF_UP_FROM_Z",
 	"ISIS_DISABLE", "IF_DOWN_FROM_Z",
 };
diff --git a/isisd/isis_dlpi.c b/isisd/isis_dlpi.c
index 7d3dfcb01..ea16f4af7 100644
--- a/isisd/isis_dlpi.c
+++ b/isisd/isis_dlpi.c
@@ -54,10 +54,13 @@ static t_uscalar_t dlpi_ctl[1024]; /* DLPI control messages */
  * ISO 10589 - 8.4.8
  */
 
-uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
-uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
-uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
-uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
+static const uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
+static const uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
+static const uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
+#if 0
+/* missing support for ES-IS on Solaris */
+static const uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
+#endif
 
 static uint8_t sock_buff[8192];
 
diff --git a/isisd/isis_pfpacket.c b/isisd/isis_pfpacket.c
index 69ac3fc55..28a1488c3 100644
--- a/isisd/isis_pfpacket.c
+++ b/isisd/isis_pfpacket.c
@@ -45,7 +45,7 @@
 #include "privs.h"
 
 /* tcpdump -i eth0 'isis' -dd */
-static struct sock_filter isisfilter[] = {
+static const struct sock_filter isisfilter[] = {
 	/* NB: we're in SOCK_DGRAM, so src/dst mac + length are stripped
 	 * off!
 	 * (OTOH it's a bit more lower-layer agnostic and might work
@@ -57,9 +57,9 @@ static struct sock_filter isisfilter[] = {
 	{0x6, 0, 0, 0x00040000},       {0x6, 0, 0, 0x00000000},
 };
 
-static struct sock_fprog bpf = {
+static const struct sock_fprog bpf = {
 	.len = array_size(isisfilter),
-	.filter = isisfilter,
+	.filter = (struct sock_filter *)isisfilter,
 };
 
 /*
@@ -67,10 +67,10 @@ static struct sock_fprog bpf = {
  * ISO 10589 - 8.4.8
  */
 
-uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
-uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
-uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
-uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
+static const uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
+static const uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
+static const uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
+static const uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
 
 static uint8_t discard_buff[8192];
 
diff --git a/isisd/isis_te.c b/isisd/isis_te.c
index 9871d2bcb..133707d61 100644
--- a/isisd/isis_te.c
+++ b/isisd/isis_te.c
@@ -60,8 +60,6 @@
 #include "isisd/isis_te.h"
 #include "isisd/isis_zebra.h"
 
-const char *mode2text[] = {"Disable", "Area", "AS", "Emulate"};
-
 /*------------------------------------------------------------------------*
  * Followings are control functions for MPLS-TE parameters management.
  *------------------------------------------------------------------------*/
diff --git a/isisd/isis_tlvs.c b/isisd/isis_tlvs.c
index 442442152..df6280e5c 100644
--- a/isisd/isis_tlvs.c
+++ b/isisd/isis_tlvs.c
@@ -88,7 +88,7 @@ struct pack_order_entry {
 		.what_to_pack = offsetof(struct isis_tlvs, w),                 \
 	}
 
-static struct pack_order_entry pack_order[] = {
+static const struct pack_order_entry pack_order[] = {
 	PACK_ENTRY(OLDSTYLE_REACH, ISIS_ITEMS, oldstyle_reach),
 	PACK_ENTRY(LAN_NEIGHBORS, ISIS_ITEMS, lan_neighbor),
 	PACK_ENTRY(LSP_ENTRY, ISIS_ITEMS, lsp_entries),
@@ -106,7 +106,7 @@ static struct pack_order_entry pack_order[] = {
 
 /* This is a forward definition. The table is actually initialized
  * in at the bottom. */
-static const struct tlv_ops *tlv_table[ISIS_CONTEXT_MAX][ISIS_TLV_MAX];
+static const struct tlv_ops *const tlv_table[ISIS_CONTEXT_MAX][ISIS_TLV_MAX];
 
 /* End of _ops forward definition. */
 
@@ -1003,7 +1003,7 @@ static void free_items(enum isis_tlv_context context, enum isis_tlv_type type,
 static int pack_items_(uint16_t mtid, enum isis_tlv_context context,
 		       enum isis_tlv_type type, struct isis_item_list *items,
 		       struct stream *s, struct isis_tlvs **fragment_tlvs,
-		       struct pack_order_entry *pe,
+		       const struct pack_order_entry *pe,
 		       struct isis_tlvs *(*new_fragment)(struct list *l),
 		       struct list *new_fragment_arg);
 #define pack_items(...) pack_items_(ISIS_MT_IPV4_UNICAST, __VA_ARGS__)
@@ -3095,7 +3095,7 @@ static void free_items(enum isis_tlv_context context, enum isis_tlv_type type,
 static int pack_item(enum isis_tlv_context context, enum isis_tlv_type type,
 		     struct isis_item *i, struct stream *s,
 		     struct isis_tlvs **fragment_tlvs,
-		     struct pack_order_entry *pe, uint16_t mtid)
+		     const struct pack_order_entry *pe, uint16_t mtid)
 {
 	const struct tlv_ops *ops = tlv_table[context][type];
 
@@ -3107,7 +3107,8 @@ static int pack_item(enum isis_tlv_context context, enum isis_tlv_type type,
 	return 1;
 }
 
-static void add_item_to_fragment(struct isis_item *i, struct pack_order_entry *pe,
+static void add_item_to_fragment(struct isis_item *i,
+				 const struct pack_order_entry *pe,
 				 struct isis_tlvs *fragment_tlvs, uint16_t mtid)
 {
 	struct isis_item_list *l;
@@ -3126,7 +3127,7 @@ static void add_item_to_fragment(struct isis_item *i, struct pack_order_entry *p
 static int pack_items_(uint16_t mtid, enum isis_tlv_context context,
 		       enum isis_tlv_type type, struct isis_item_list *items,
 		       struct stream *s, struct isis_tlvs **fragment_tlvs,
-		       struct pack_order_entry *pe,
+		       const struct pack_order_entry *pe,
 		       struct isis_tlvs *(*new_fragment)(struct list *l),
 		       struct list *new_fragment_arg)
 {
@@ -3401,7 +3402,7 @@ static void format_mt_items(enum isis_tlv_context context,
 static int pack_mt_items(enum isis_tlv_context context, enum isis_tlv_type type,
 			 struct isis_mt_item_list *m, struct stream *s,
 			 struct isis_tlvs **fragment_tlvs,
-			 struct pack_order_entry *pe,
+			 const struct pack_order_entry *pe,
 			 struct isis_tlvs *(*new_fragment)(struct list *l),
 			 struct list *new_fragment_arg)
 {
@@ -3734,7 +3735,7 @@ static void update_auth(struct isis_tlvs *tlvs, struct stream *s, bool is_lsp)
 	}
 }
 
-static int handle_pack_entry(struct pack_order_entry *pe,
+static int handle_pack_entry(const struct pack_order_entry *pe,
 			     struct isis_tlvs *tlvs, struct stream *stream,
 			     struct isis_tlvs **fragment_tlvs,
 			     struct isis_tlvs *(*new_fragment)(struct list *l),
@@ -4079,7 +4080,7 @@ TLV_OPS(router_cap, "TLV 242 Router Capability");
 ITEM_SUBTLV_OPS(prefix_sid, "Sub-TLV 3 SR Prefix-SID");
 SUBTLV_OPS(ipv6_source_prefix, "Sub-TLV 22 IPv6 Source Prefix");
 
-static const struct tlv_ops *tlv_table[ISIS_CONTEXT_MAX][ISIS_TLV_MAX] = {
+static const struct tlv_ops *const tlv_table[ISIS_CONTEXT_MAX][ISIS_TLV_MAX] = {
 	[ISIS_CONTEXT_LSP] = {
 		[ISIS_TLV_AREA_ADDRESSES] = &tlv_area_address_ops,
 		[ISIS_TLV_OLDSTYLE_REACH] = &tlv_oldstyle_reach_ops,
diff --git a/ldpd/ldpd.c b/ldpd/ldpd.c
index 533fc9ac8..dcbcf8ce5 100644
--- a/ldpd/ldpd.c
+++ b/ldpd/ldpd.c
@@ -120,7 +120,7 @@ char ctl_sock_path[MAXPATHLEN];
 
 /* LDPd options. */
 #define OPTION_CTLSOCK 1001
-static struct option longopts[] =
+static const struct option longopts[] =
 {
 	{ "ctl_socket",  required_argument, NULL, OPTION_CTLSOCK},
 	{ "instance",    required_argument, NULL, 'n'},
diff --git a/ldpd/neighbor.c b/ldpd/neighbor.c
index 78a6131ca..ae51490c0 100644
--- a/ldpd/neighbor.c
+++ b/ldpd/neighbor.c
@@ -49,7 +49,7 @@ RB_GENERATE(nbr_addr_head, nbr, addr_tree, nbr_addr_compare)
 RB_GENERATE(nbr_pid_head, nbr, pid_tree, nbr_pid_compare)
 RB_GENERATE(nbrp_head, nbr_params, entry, nbr_params_compare)
 
-struct {
+const struct {
 	int		state;
 	enum nbr_event	event;
 	enum nbr_action	action;
diff --git a/lib/frr_pthread.c b/lib/frr_pthread.c
index 5c71fac10..55f0b55ed 100644
--- a/lib/frr_pthread.c
+++ b/lib/frr_pthread.c
@@ -39,7 +39,7 @@ static int fpt_halt(struct frr_pthread *fpt, void **res);
 static void frr_pthread_destroy_nolock(struct frr_pthread *fpt);
 
 /* default frr_pthread attributes */
-struct frr_pthread_attr frr_pthread_attr_default = {
+const struct frr_pthread_attr frr_pthread_attr_default = {
 	.start = fpt_run,
 	.stop = fpt_halt,
 };
@@ -74,7 +74,7 @@ void frr_pthread_finish(void)
 	}
 }
 
-struct frr_pthread *frr_pthread_new(struct frr_pthread_attr *attr,
+struct frr_pthread *frr_pthread_new(const struct frr_pthread_attr *attr,
 				    const char *name, const char *os_name)
 {
 	struct frr_pthread *fpt = NULL;
diff --git a/lib/frr_pthread.h b/lib/frr_pthread.h
index f70c8a0db..89519abae 100644
--- a/lib/frr_pthread.h
+++ b/lib/frr_pthread.h
@@ -99,7 +99,7 @@ struct frr_pthread {
 	char os_name[OS_THREAD_NAMELEN];
 };
 
-extern struct frr_pthread_attr frr_pthread_attr_default;
+extern const struct frr_pthread_attr frr_pthread_attr_default;
 
 /*
  * Initializes this module.
@@ -133,7 +133,7 @@ void frr_pthread_finish(void);
  * @param os_name - 16 characters (including '\0') thread name to set in os,
  * @return the created frr_pthread upon success, or NULL upon failure
  */
-struct frr_pthread *frr_pthread_new(struct frr_pthread_attr *attr,
+struct frr_pthread *frr_pthread_new(const struct frr_pthread_attr *attr,
 				    const char *name, const char *os_name);
 
 /*
diff --git a/lib/nexthop.c b/lib/nexthop.c
index 73c2de0cd..d05fa8e6d 100644
--- a/lib/nexthop.c
+++ b/lib/nexthop.c
@@ -200,7 +200,7 @@ int nexthop_same_firsthop(struct nexthop *next1, struct nexthop *next2)
  */
 const char *nexthop_type_to_str(enum nexthop_types_t nh_type)
 {
-	static const char *desc[] = {
+	static const char *const desc[] = {
 		"none",		 "Directly connected",
 		"IPv4 nexthop",  "IPv4 nexthop with ifindex",
 		"IPv6 nexthop",  "IPv6 nexthop with ifindex",
diff --git a/lib/printfrr.h b/lib/printfrr.h
index 95dace702..f9584bcac 100644
--- a/lib/printfrr.h
+++ b/lib/printfrr.h
@@ -124,7 +124,7 @@ void printfrr_ext_reg(const struct printfrr_ext *);
 #define printfrr_ext_autoreg_p(matchs, print_fn)                               \
 	static ssize_t print_fn(char *, size_t, const char *, int,             \
 				const void *);                                 \
-	static struct printfrr_ext _printext_##print_fn = {                    \
+	static const struct printfrr_ext _printext_##print_fn = {              \
 		.match = matchs,                                               \
 		.print_ptr = print_fn,                                         \
 	};                                                                     \
@@ -136,7 +136,7 @@ void printfrr_ext_reg(const struct printfrr_ext *);
 
 #define printfrr_ext_autoreg_i(matchs, print_fn)                               \
 	static ssize_t print_fn(char *, size_t, const char *, int, uintmax_t); \
-	static struct printfrr_ext _printext_##print_fn = {                    \
+	static const struct printfrr_ext _printext_##print_fn = {              \
 		.match = matchs,                                               \
 		.print_int = print_fn,                                         \
 	};                                                                     \
diff --git a/lib/table.h b/lib/table.h
index 7a69c1664..7743d5168 100644
--- a/lib/table.h
+++ b/lib/table.h
@@ -45,7 +45,7 @@ struct route_table;
  * Function vector that can be used by a client to customize the
  * behavior of one or more route tables.
  */
-typedef struct route_table_delegate_t_ route_table_delegate_t;
+typedef const struct route_table_delegate_t_ route_table_delegate_t;
 
 typedef struct route_node *(*route_table_create_node_func_t)(
 	route_table_delegate_t *, struct route_table *);
diff --git a/lib/termtable.c b/lib/termtable.c
index b59c1118f..b22a1ad38 100644
--- a/lib/termtable.c
+++ b/lib/termtable.c
@@ -27,7 +27,7 @@
 DEFINE_MTYPE_STATIC(LIB, TTABLE, "ASCII table")
 
 /* clang-format off */
-struct ttable_style ttable_styles[] = {
+const struct ttable_style ttable_styles[] = {
 	{	// default ascii
 		.corner = '+',
 		.rownums_on = false,
@@ -99,7 +99,7 @@ void ttable_del(struct ttable *tt)
 	XFREE(MTYPE_TTABLE, tt);
 }
 
-struct ttable *ttable_new(struct ttable_style *style)
+struct ttable *ttable_new(const struct ttable_style *style)
 {
 	struct ttable *tt;
 
diff --git a/lib/termtable.h b/lib/termtable.h
index 4f7c595ce..698cc7346 100644
--- a/lib/termtable.h
+++ b/lib/termtable.h
@@ -80,7 +80,7 @@ struct ttable {
 #define TTSTYLE_ASCII 0
 #define TTSTYLE_BLANK 1
 
-extern struct ttable_style ttable_styles[2];
+extern const struct ttable_style ttable_styles[2];
 
 /**
  * Creates a new table with the default style, which looks like this:
@@ -95,7 +95,7 @@ extern struct ttable_style ttable_styles[2];
  *
  * @return the created table
  */
-struct ttable *ttable_new(struct ttable_style *tts);
+struct ttable *ttable_new(const struct ttable_style *tts);
 
 /**
  * Deletes a table and releases all associated resources.
diff --git a/lib/thread.c b/lib/thread.c
index 649fe500c..651d26dfb 100644
--- a/lib/thread.c
+++ b/lib/thread.c
@@ -66,7 +66,7 @@ DECLARE_HEAP(thread_timer_list, struct thread, timeritem,
 
 #define AWAKEN(m)                                                              \
 	do {                                                                   \
-		static unsigned char wakebyte = 0x01;                          \
+		const unsigned char wakebyte = 0x01;                           \
 		write(m->io_pipe[1], &wakebyte, 1);                            \
 	} while (0);
 
diff --git a/nhrpd/nhrp_peer.c b/nhrpd/nhrp_peer.c
index ca309f250..3a74b7569 100644
--- a/nhrpd/nhrp_peer.c
+++ b/nhrpd/nhrp_peer.c
@@ -657,7 +657,7 @@ enum packet_type_t {
 	PACKET_INDICATION,
 };
 
-static struct {
+static const struct {
 	enum packet_type_t type;
 	const char *name;
 	void (*handler)(struct nhrp_packet_parser *);
diff --git a/ospf6d/ospf6_abr.c b/ospf6d/ospf6_abr.c
index 0ce53143b..ff82bb179 100644
--- a/ospf6d/ospf6_abr.c
+++ b/ospf6d/ospf6_abr.c
@@ -1420,7 +1420,7 @@ void install_element_ospf6_debug_abr(void)
 	install_element(CONFIG_NODE, &no_debug_ospf6_abr_cmd);
 }
 
-struct ospf6_lsa_handler inter_prefix_handler = {
+static const struct ospf6_lsa_handler inter_prefix_handler = {
 	.lh_type = OSPF6_LSTYPE_INTER_PREFIX,
 	.lh_name = "Inter-Prefix",
 	.lh_short_name = "IAP",
@@ -1428,7 +1428,7 @@ struct ospf6_lsa_handler inter_prefix_handler = {
 	.lh_get_prefix_str = ospf6_inter_area_prefix_lsa_get_prefix_str,
 	.lh_debug = 0};
 
-struct ospf6_lsa_handler inter_router_handler = {
+static const struct ospf6_lsa_handler inter_router_handler = {
 	.lh_type = OSPF6_LSTYPE_INTER_ROUTER,
 	.lh_name = "Inter-Router",
 	.lh_short_name = "IAR",
diff --git a/ospf6d/ospf6_interface.c b/ospf6d/ospf6_interface.c
index a56ba0a69..93265afc4 100644
--- a/ospf6d/ospf6_interface.c
+++ b/ospf6d/ospf6_interface.c
@@ -52,7 +52,7 @@ DEFINE_HOOK(ospf6_interface_change,
 
 unsigned char conf_debug_ospf6_interface = 0;
 
-const char *ospf6_interface_state_str[] = {
+const char *const ospf6_interface_state_str[] = {
 	"None",    "Down", "Loopback", "Waiting", "PointToPoint",
 	"DROther", "BDR",  "DR",       NULL};
 
diff --git a/ospf6d/ospf6_interface.h b/ospf6d/ospf6_interface.h
index 53a8910f4..05ba698a1 100644
--- a/ospf6d/ospf6_interface.h
+++ b/ospf6d/ospf6_interface.h
@@ -148,7 +148,7 @@ DECLARE_QOBJ_TYPE(ospf6_interface)
 #define OSPF6_INTERFACE_DR               7
 #define OSPF6_INTERFACE_MAX              8
 
-extern const char *ospf6_interface_state_str[];
+extern const char *const ospf6_interface_state_str[];
 
 /* flags */
 #define OSPF6_INTERFACE_DISABLE      0x01
diff --git a/ospf6d/ospf6_intra.c b/ospf6d/ospf6_intra.c
index 7ae7d682b..0fde997a2 100644
--- a/ospf6d/ospf6_intra.c
+++ b/ospf6d/ospf6_intra.c
@@ -2232,31 +2232,31 @@ void ospf6_intra_brouter_calculation(struct ospf6_area *oa)
 			  __PRETTY_FUNCTION__, oa->name);
 }
 
-struct ospf6_lsa_handler router_handler = {.lh_type = OSPF6_LSTYPE_ROUTER,
-					   .lh_name = "Router",
-					   .lh_short_name = "Rtr",
-					   .lh_show = ospf6_router_lsa_show,
-					   .lh_get_prefix_str =
-						   ospf6_router_lsa_get_nbr_id,
-					   .lh_debug = 0};
-
-struct ospf6_lsa_handler network_handler = {.lh_type = OSPF6_LSTYPE_NETWORK,
-					    .lh_name = "Network",
-					    .lh_short_name = "Net",
-					    .lh_show = ospf6_network_lsa_show,
-					    .lh_get_prefix_str =
-						    ospf6_network_lsa_get_ar_id,
-					    .lh_debug = 0};
-
-struct ospf6_lsa_handler link_handler = {.lh_type = OSPF6_LSTYPE_LINK,
-					 .lh_name = "Link",
-					 .lh_short_name = "Lnk",
-					 .lh_show = ospf6_link_lsa_show,
-					 .lh_get_prefix_str =
-						 ospf6_link_lsa_get_prefix_str,
-					 .lh_debug = 0};
-
-struct ospf6_lsa_handler intra_prefix_handler = {
+static const struct ospf6_lsa_handler router_handler = {
+	.lh_type = OSPF6_LSTYPE_ROUTER,
+	.lh_name = "Router",
+	.lh_short_name = "Rtr",
+	.lh_show = ospf6_router_lsa_show,
+	.lh_get_prefix_str = ospf6_router_lsa_get_nbr_id,
+	.lh_debug = 0};
+
+static const struct ospf6_lsa_handler network_handler = {
+	.lh_type = OSPF6_LSTYPE_NETWORK,
+	.lh_name = "Network",
+	.lh_short_name = "Net",
+	.lh_show = ospf6_network_lsa_show,
+	.lh_get_prefix_str = ospf6_network_lsa_get_ar_id,
+	.lh_debug = 0};
+
+static const struct ospf6_lsa_handler link_handler = {
+	.lh_type = OSPF6_LSTYPE_LINK,
+	.lh_name = "Link",
+	.lh_short_name = "Lnk",
+	.lh_show = ospf6_link_lsa_show,
+	.lh_get_prefix_str = ospf6_link_lsa_get_prefix_str,
+	.lh_debug = 0};
+
+static const struct ospf6_lsa_handler intra_prefix_handler = {
 	.lh_type = OSPF6_LSTYPE_INTRA_PREFIX,
 	.lh_name = "Intra-Prefix",
 	.lh_short_name = "INP",
diff --git a/ospf6d/ospf6_neighbor.c b/ospf6d/ospf6_neighbor.c
index 4318db522..1e90d4b9b 100644
--- a/ospf6d/ospf6_neighbor.c
+++ b/ospf6d/ospf6_neighbor.c
@@ -51,10 +51,16 @@ DEFINE_HOOK(ospf6_neighbor_change,
 
 unsigned char conf_debug_ospf6_neighbor = 0;
 
-const char *ospf6_neighbor_state_str[] = {
+const char *const ospf6_neighbor_state_str[] = {
 	"None",    "Down",     "Attempt", "Init", "Twoway",
 	"ExStart", "ExChange", "Loading", "Full", NULL};
 
+const char *const ospf6_neighbor_event_str[] = {
+	"NoEvent",      "HelloReceived", "2-WayReceived",   "NegotiationDone",
+	"ExchangeDone", "LoadingDone",   "AdjOK?",	  "SeqNumberMismatch",
+	"BadLSReq",     "1-WayReceived", "InactivityTimer",
+};
+
 int ospf6_neighbor_cmp(void *va, void *vb)
 {
 	struct ospf6_neighbor *ona = (struct ospf6_neighbor *)va;
diff --git a/ospf6d/ospf6_neighbor.h b/ospf6d/ospf6_neighbor.h
index 840683cc2..e221e9d82 100644
--- a/ospf6d/ospf6_neighbor.h
+++ b/ospf6d/ospf6_neighbor.h
@@ -123,11 +123,7 @@ struct ospf6_neighbor {
 #define OSPF6_NEIGHBOR_EVENT_INACTIVITY_TIMER    10
 #define OSPF6_NEIGHBOR_EVENT_MAX_EVENT           11
 
-static const char *ospf6_neighbor_event_str[] = {
-	"NoEvent",      "HelloReceived", "2-WayReceived",   "NegotiationDone",
-	"ExchangeDone", "LoadingDone",   "AdjOK?",	  "SeqNumberMismatch",
-	"BadLSReq",     "1-WayReceived", "InactivityTimer",
-};
+extern const char *const ospf6_neighbor_event_str[];
 
 static inline const char *ospf6_neighbor_event_string(int event)
 {
@@ -138,7 +134,7 @@ static inline const char *ospf6_neighbor_event_string(int event)
 	return OSPF6_NEIGHBOR_UNKNOWN_EVENT_STRING;
 }
 
-extern const char *ospf6_neighbor_state_str[];
+extern const char *const ospf6_neighbor_state_str[];
 
 
 /* Function Prototypes */
diff --git a/ospf6d/ospf6_route.c b/ospf6d/ospf6_route.c
index 441a6f367..28b15769d 100644
--- a/ospf6d/ospf6_route.c
+++ b/ospf6d/ospf6_route.c
@@ -147,19 +147,19 @@ void ospf6_linkstate_prefix2str(struct prefix *prefix, char *buf, int size)
 }
 
 /* Global strings for logging */
-const char *ospf6_dest_type_str[OSPF6_DEST_TYPE_MAX] = {
+const char *const ospf6_dest_type_str[OSPF6_DEST_TYPE_MAX] = {
 	"Unknown", "Router", "Network", "Discard", "Linkstate", "AddressRange",
 };
 
-const char *ospf6_dest_type_substr[OSPF6_DEST_TYPE_MAX] = {
+const char *const ospf6_dest_type_substr[OSPF6_DEST_TYPE_MAX] = {
 	"?", "R", "N", "D", "L", "A",
 };
 
-const char *ospf6_path_type_str[OSPF6_PATH_TYPE_MAX] = {
+const char *const ospf6_path_type_str[OSPF6_PATH_TYPE_MAX] = {
 	"Unknown", "Intra-Area", "Inter-Area", "External-1", "External-2",
 };
 
-const char *ospf6_path_type_substr[OSPF6_PATH_TYPE_MAX] = {
+const char *const ospf6_path_type_substr[OSPF6_PATH_TYPE_MAX] = {
 	"??", "IA", "IE", "E1", "E2",
 };
 
diff --git a/ospf6d/ospf6_route.h b/ospf6d/ospf6_route.h
index 02002533e..13b01a348 100644
--- a/ospf6d/ospf6_route.h
+++ b/ospf6d/ospf6_route.h
@@ -215,8 +215,8 @@ struct ospf6_route_table {
 #define OSPF6_ROUTE_TABLE_CREATE(s, t)                                         \
 	ospf6_route_table_create(OSPF6_SCOPE_TYPE_##s, OSPF6_TABLE_TYPE_##t)
 
-extern const char *ospf6_dest_type_str[OSPF6_DEST_TYPE_MAX];
-extern const char *ospf6_dest_type_substr[OSPF6_DEST_TYPE_MAX];
+extern const char *const ospf6_dest_type_str[OSPF6_DEST_TYPE_MAX];
+extern const char *const ospf6_dest_type_substr[OSPF6_DEST_TYPE_MAX];
 #define OSPF6_DEST_TYPE_NAME(x)                                                \
 	(0 < (x) && (x) < OSPF6_DEST_TYPE_MAX ? ospf6_dest_type_str[(x)]       \
 					      : ospf6_dest_type_str[0])
@@ -224,8 +224,8 @@ extern const char *ospf6_dest_type_substr[OSPF6_DEST_TYPE_MAX];
 	(0 < (x) && (x) < OSPF6_DEST_TYPE_MAX ? ospf6_dest_type_substr[(x)]    \
 					      : ospf6_dest_type_substr[0])
 
-extern const char *ospf6_path_type_str[OSPF6_PATH_TYPE_MAX];
-extern const char *ospf6_path_type_substr[OSPF6_PATH_TYPE_MAX];
+extern const char *const ospf6_path_type_str[OSPF6_PATH_TYPE_MAX];
+extern const char *const ospf6_path_type_substr[OSPF6_PATH_TYPE_MAX];
 #define OSPF6_PATH_TYPE_NAME(x)                                                \
 	(0 < (x) && (x) < OSPF6_PATH_TYPE_MAX ? ospf6_path_type_str[(x)]       \
 					      : ospf6_path_type_str[0])
diff --git a/ospf6d/ospf6_spf.c b/ospf6d/ospf6_spf.c
index aa4a99517..966ef4482 100644
--- a/ospf6d/ospf6_spf.c
+++ b/ospf6d/ospf6_spf.c
@@ -435,7 +435,7 @@ void ospf6_spf_table_finish(struct ospf6_route_table *result_table)
 	}
 }
 
-static const char *ospf6_spf_reason_str[] = {
+static const char *const ospf6_spf_reason_str[] = {
 	"R+", "R-", "N+", "N-", "L+", "L-", "R*", "N*",
 };
 
diff --git a/ospfd/ospf_ism.c b/ospfd/ospf_ism.c
index 419081fe5..e394b6f47 100644
--- a/ospfd/ospf_ism.c
+++ b/ospfd/ospf_ism.c
@@ -418,7 +418,7 @@ static int ism_ignore(struct ospf_interface *oi)
 }
 
 /* Interface State Machine */
-struct {
+const struct {
 	int (*func)(struct ospf_interface *);
 	int next_state;
 } ISM[OSPF_ISM_STATE_MAX][OSPF_ISM_EVENT_MAX] = {
@@ -512,7 +512,7 @@ struct {
 	},
 };
 
-static const char *ospf_ism_event_str[] = {
+static const char *const ospf_ism_event_str[] = {
 	"NoEvent",	"InterfaceUp", "WaitTimer", "BackupSeen",
 	"NeighborChange", "LoopInd",     "UnLoopInd", "InterfaceDown",
 };
diff --git a/ospfd/ospf_lsa.c b/ospfd/ospf_lsa.c
index 3e3f28802..6eec87c93 100644
--- a/ospfd/ospf_lsa.c
+++ b/ospfd/ospf_lsa.c
@@ -290,7 +290,7 @@ void ospf_lsa_data_free(struct lsa_header *lsah)
 
 const char *dump_lsa_key(struct ospf_lsa *lsa)
 {
-	static char buf[] = {"Type255,id(255.255.255.255),ar(255.255.255.255)"};
+	static char buf[sizeof("Type255,id(255.255.255.255),ar(255.255.255.255)")+1];
 	struct lsa_header *lsah;
 
 	if (lsa != NULL && (lsah = lsa->data) != NULL) {
diff --git a/ospfd/ospf_main.c b/ospfd/ospf_main.c
index f6cd0fc83..a542b4da8 100644
--- a/ospfd/ospf_main.c
+++ b/ospfd/ospf_main.c
@@ -72,9 +72,11 @@ struct zebra_privs_t ospfd_privs = {
 	.cap_num_i = 0};
 
 /* OSPFd options. */
-struct option longopts[] = {{"instance", required_argument, NULL, 'n'},
-			    {"apiserver", no_argument, NULL, 'a'},
-			    {0}};
+const struct option longopts[] = {
+	{"instance", required_argument, NULL, 'n'},
+	{"apiserver", no_argument, NULL, 'a'},
+	{0}
+};
 
 /* OSPFd program name */
 
diff --git a/ospfd/ospf_nsm.c b/ospfd/ospf_nsm.c
index 9f6be3cbc..0fc2cd60f 100644
--- a/ospfd/ospf_nsm.c
+++ b/ospfd/ospf_nsm.c
@@ -399,7 +399,7 @@ static int nsm_kill_nbr(struct ospf_neighbor *nbr)
 }
 
 /* Neighbor State Machine */
-struct {
+const struct {
 	int (*func)(struct ospf_neighbor *);
 	int next_state;
 } NSM[OSPF_NSM_STATE_MAX][OSPF_NSM_EVENT_MAX] = {
@@ -575,7 +575,7 @@ struct {
 	},
 };
 
-static const char *ospf_nsm_event_str[] = {
+static const char *const ospf_nsm_event_str[] = {
 	"NoEvent",	   "PacketReceived",  "Start",
 	"2-WayReceived",     "NegotiationDone", "ExchangeDone",
 	"BadLSReq",	  "LoadingDone",     "AdjOK?",
diff --git a/ospfd/ospf_route.c b/ospfd/ospf_route.c
index da83c1dda..6cabc0c98 100644
--- a/ospfd/ospf_route.c
+++ b/ospfd/ospf_route.c
@@ -622,8 +622,10 @@ void ospf_intra_add_stub(struct route_table *rt, struct router_lsa_link *link,
 		zlog_debug("ospf_intra_add_stub(): Stop");
 }
 
-const char *ospf_path_type_str[] = {"unknown-type", "intra-area", "inter-area",
-				    "type1-external", "type2-external"};
+static const char *const ospf_path_type_str[] = {
+	"unknown-type", "intra-area", "inter-area", "type1-external",
+	"type2-external"
+};
 
 void ospf_route_table_dump(struct route_table *rt)
 {
diff --git a/ospfd/ospf_te.c b/ospfd/ospf_te.c
index e68363663..8da99843e 100644
--- a/ospfd/ospf_te.c
+++ b/ospfd/ospf_te.c
@@ -69,7 +69,7 @@
  */
 struct ospf_mpls_te OspfMplsTE;
 
-const char *mode2text[] = {"Off", "AS", "Area"};
+static const char *const mode2text[] = {"Off", "AS", "Area"};
 
 /*------------------------------------------------------------------------*
  * Followings are initialize/terminate functions for MPLS-TE handling.
diff --git a/ospfd/ospf_vty.c b/ospfd/ospf_vty.c
index d11c34f24..4c97615ed 100644
--- a/ospfd/ospf_vty.c
+++ b/ospfd/ospf_vty.c
@@ -53,7 +53,7 @@
 #include "ospfd/ospf_dump.h"
 #include "ospfd/ospf_bfd.h"
 
-static const char *ospf_network_type_str[] = {
+static const char *const ospf_network_type_str[] = {
 	"Null",	"POINTOPOINT", "BROADCAST", "NBMA", "POINTOMULTIPOINT",
 	"VIRTUALLINK", "LOOPBACK"};
 
@@ -2622,11 +2622,14 @@ ALIAS(no_ospf_write_multiplier, no_write_multiplier_cmd,
       "Write multiplier\n"
       "Maximum number of interface serviced per write\n")
 
-const char *ospf_abr_type_descr_str[] = {"Unknown", "Standard (RFC2328)",
-					 "Alternative IBM", "Alternative Cisco",
-					 "Alternative Shortcut"};
+static const char *const ospf_abr_type_descr_str[] = {
+	"Unknown", "Standard (RFC2328)", "Alternative IBM",
+	"Alternative Cisco", "Alternative Shortcut"
+};
 
-const char *ospf_shortcut_mode_descr_str[] = {"Default", "Enabled", "Disabled"};
+static const char *const ospf_shortcut_mode_descr_str[] = {
+	"Default", "Enabled", "Disabled"
+};
 
 static void show_ip_ospf_area(struct vty *vty, struct ospf_area *area,
 			      json_object *json_areas, bool use_json)
@@ -5767,7 +5770,7 @@ static int show_lsa_summary(struct vty *vty, struct ospf_lsa *lsa, int self)
 	return 0;
 }
 
-static const char *show_database_desc[] = {
+static const char *const show_database_desc[] = {
 	"unknown",
 	"Router Link States",
 	"Net Link States",
@@ -5782,7 +5785,7 @@ static const char *show_database_desc[] = {
 	"AS-external Opaque-LSA",
 };
 
-static const char *show_database_header[] = {
+static const char *const show_database_header[] = {
 	"",
 	"Link ID         ADV Router      Age  Seq#       CkSum  Link count",
 	"Link ID         ADV Router      Age  Seq#       CkSum",
@@ -5834,7 +5837,7 @@ static void show_ip_ospf_database_header(struct vty *vty, struct ospf_lsa *lsa)
 	vty_out(vty, "  Length: %d\n\n", ntohs(lsa->data->length));
 }
 
-const char *link_type_desc[] = {
+static const char *const link_type_desc[] = {
 	"(null)",
 	"another Router (point-to-point)",
 	"a Transit Network",
@@ -5842,12 +5845,12 @@ const char *link_type_desc[] = {
 	"a Virtual Link",
 };
 
-const char *link_id_desc[] = {
+static const char *const link_id_desc[] = {
 	"(null)", "Neighboring Router ID", "Designated Router address",
 	"Net",    "Neighboring Router ID",
 };
 
-const char *link_data_desc[] = {
+static const char *const link_data_desc[] = {
 	"(null)",       "Router Interface address", "Router Interface address",
 	"Network Mask", "Router Interface address",
 };
@@ -6047,7 +6050,7 @@ static int show_opaque_lsa_detail(struct vty *vty, struct ospf_lsa *lsa)
 	return 0;
 }
 
-int (*show_function[])(struct vty *, struct ospf_lsa *) = {
+int (*const show_function[])(struct vty *, struct ospf_lsa *) = {
 	NULL,
 	show_router_lsa_detail,
 	show_network_lsa_detail,
@@ -9646,7 +9649,7 @@ DEFUN (show_ip_ospf_vrfs,
 	struct ospf *ospf = NULL;
 	struct listnode *node = NULL;
 	int count = 0;
-	static char header[] = "Name                       Id     RouterId  ";
+	static const char header[] = "Name                       Id     RouterId  ";
 
 	if (uj) {
 		json = json_object_new_object();
@@ -9703,16 +9706,23 @@ DEFUN (show_ip_ospf_vrfs,
 	return CMD_SUCCESS;
 }
 
-const char *ospf_abr_type_str[] = {"unknown", "standard", "ibm", "cisco",
-				   "shortcut"};
+static const char *const ospf_abr_type_str[] = {
+	"unknown", "standard", "ibm", "cisco", "shortcut"
+};
 
-const char *ospf_shortcut_mode_str[] = {"default", "enable", "disable"};
+static const char *const ospf_shortcut_mode_str[] = {
+	"default", "enable", "disable"
+};
 
-const char *ospf_int_type_str[] = {"unknown", /* should never be used. */
-				   "point-to-point", "broadcast",
-				   "non-broadcast",  "point-to-multipoint",
-				   "virtual-link", /* should never be used. */
-				   "loopback"};
+static const char *const ospf_int_type_str[] = {
+	"unknown", /* should never be used. */
+	"point-to-point",
+	"broadcast",
+	"non-broadcast",
+	"point-to-multipoint",
+	"virtual-link", /* should never be used. */
+	"loopback"
+};
 
 static int config_write_interface_one(struct vty *vty, struct vrf *vrf)
 {
diff --git a/pbrd/pbr_map.c b/pbrd/pbr_map.c
index 4df0c790b..7e34066b4 100644
--- a/pbrd/pbr_map.c
+++ b/pbrd/pbr_map.c
@@ -145,7 +145,7 @@ static void pbr_map_pbrms_uninstall(struct pbr_map_sequence *pbrms)
 	pbr_map_pbrms_update_common(pbrms, false);
 }
 
-static const char *pbr_map_reason_str[] = {
+static const char *const pbr_map_reason_str[] = {
 	"Invalid NH-group",     "Invalid NH",	 "No Nexthops",
 	"Both NH and NH-Group", "Invalid Src or Dst", "Invalid VRF",
 	"Deleting Sequence",
diff --git a/pimd/pim_mroute.c b/pimd/pim_mroute.c
index ec06cd734..2859d26eb 100644
--- a/pimd/pim_mroute.c
+++ b/pimd/pim_mroute.c
@@ -147,7 +147,7 @@ static int pim_mroute_set(struct pim_instance *pim, int enable)
 	return 0;
 }
 
-static const char *igmpmsgtype2str[IGMPMSG_WRVIFWHOLE + 1] = {
+static const char *const igmpmsgtype2str[IGMPMSG_WRVIFWHOLE + 1] = {
 	"<unknown_upcall?>", "NOCACHE", "WRONGVIF", "WHOLEPKT", "WRVIFWHOLE"};
 
 static int pim_mroute_msg_nocache(int fd, struct interface *ifp,
diff --git a/vrrpd/vrrp.c b/vrrpd/vrrp.c
index eed0e8a31..42bb154f9 100644
--- a/vrrpd/vrrp.c
+++ b/vrrpd/vrrp.c
@@ -50,13 +50,13 @@ int vrrp_autoconfig_version;
 
 struct vrrp_defaults vd;
 
-const char *vrrp_state_names[3] = {
+const char *const vrrp_state_names[3] = {
 	[VRRP_STATE_INITIALIZE] = "Initialize",
 	[VRRP_STATE_MASTER] = "Master",
 	[VRRP_STATE_BACKUP] = "Backup",
 };
 
-const char *vrrp_event_names[2] = {
+static const char *const vrrp_event_names[2] = {
 	[VRRP_EVENT_STARTUP] = "Startup",
 	[VRRP_EVENT_SHUTDOWN] = "Shutdown",
 };
@@ -1414,7 +1414,7 @@ static void vrrp_change_state_initialize(struct vrrp_router *r)
 		vrrp_zebra_radv_set(r, false);
 }
 
-void (*vrrp_change_state_handlers[])(struct vrrp_router *vr) = {
+void (*const vrrp_change_state_handlers[])(struct vrrp_router *vr) = {
 	[VRRP_STATE_MASTER] = vrrp_change_state_master,
 	[VRRP_STATE_BACKUP] = vrrp_change_state_backup,
 	[VRRP_STATE_INITIALIZE] = vrrp_change_state_initialize,
@@ -1639,7 +1639,7 @@ static int vrrp_shutdown(struct vrrp_router *r)
 	return 0;
 }
 
-static int (*vrrp_event_handlers[])(struct vrrp_router *r) = {
+static int (*const vrrp_event_handlers[])(struct vrrp_router *r) = {
 	[VRRP_EVENT_STARTUP] = vrrp_startup,
 	[VRRP_EVENT_SHUTDOWN] = vrrp_shutdown,
 };
diff --git a/vrrpd/vrrp.h b/vrrpd/vrrp.h
index 5d355d04b..79283bbb1 100644
--- a/vrrpd/vrrp.h
+++ b/vrrpd/vrrp.h
@@ -465,8 +465,7 @@ int vrrp_del_ipv6(struct vrrp_vrouter *vr, struct in6_addr v6);
 #define VRRP_EVENT_STARTUP 0
 #define VRRP_EVENT_SHUTDOWN 1
 
-extern const char *vrrp_state_names[3];
-extern const char *vrrp_event_names[2];
+extern const char *const vrrp_state_names[3];
 
 /*
  * This hook called whenever the state of a Virtual Router changes, after the
diff --git a/vrrpd/vrrp_packet.c b/vrrpd/vrrp_packet.c
index 461310c1e..e4fee2d79 100644
--- a/vrrpd/vrrp_packet.c
+++ b/vrrpd/vrrp_packet.c
@@ -33,7 +33,7 @@
 DEFINE_MTYPE_STATIC(VRRPD, VRRP_PKT, "VRRP packet")
 
 /* clang-format off */
-const char *vrrp_packet_names[16] = {
+static const char *const vrrp_packet_names[16] = {
 	[0] = "Unknown",
 	[VRRP_TYPE_ADVERTISEMENT] = "ADVERTISEMENT",
 	[2] = "Unknown",
diff --git a/vrrpd/vrrp_packet.h b/vrrpd/vrrp_packet.h
index c2ce22f00..082935f08 100644
--- a/vrrpd/vrrp_packet.h
+++ b/vrrpd/vrrp_packet.h
@@ -28,8 +28,6 @@
 
 #define VRRP_TYPE_ADVERTISEMENT 1
 
-extern const char *vrrp_packet_names[16];
-
 /*
  * Shared header for VRRPv2/v3 packets.
  */
diff --git a/watchfrr/watchfrr.c b/watchfrr/watchfrr.c
index ea5965582..4e8502107 100644
--- a/watchfrr/watchfrr.c
+++ b/watchfrr/watchfrr.c
@@ -76,7 +76,7 @@ typedef enum {
 	PHASE_WAITING_ZEBRA_UP
 } restart_phase_t;
 
-static const char *phase_str[] = {
+static const char *const phase_str[] = {
 	"Idle",
 	"Startup",
 	"Stop jobs running",
@@ -144,7 +144,7 @@ typedef enum {
 #define IS_UP(DMN)                                                             \
 	(((DMN)->state == DAEMON_UP) || ((DMN)->state == DAEMON_UNRESPONSIVE))
 
-static const char *state_str[] = {
+static const char *const state_str[] = {
 	"Init", "Down", "Connecting", "Up", "Unresponsive",
 };
 
diff --git a/zebra/ipforward_proc.c b/zebra/ipforward_proc.c
index 709d2176a..226f72293 100644
--- a/zebra/ipforward_proc.c
+++ b/zebra/ipforward_proc.c
@@ -30,7 +30,7 @@
 
 extern struct zebra_privs_t zserv_privs;
 
-char proc_net_snmp[] = "/proc/net/snmp";
+static const char proc_net_snmp[] = "/proc/net/snmp";
 
 static void dropline(FILE *fp)
 {
@@ -70,7 +70,7 @@ int ipforward(void)
 }
 
 /* char proc_ipv4_forwarding[] = "/proc/sys/net/ipv4/conf/all/forwarding"; */
-char proc_ipv4_forwarding[] = "/proc/sys/net/ipv4/ip_forward";
+static const char proc_ipv4_forwarding[] = "/proc/sys/net/ipv4/ip_forward";
 
 int ipforward_on(void)
 {
@@ -114,7 +114,8 @@ int ipforward_off(void)
 	return ipforward();
 }
 
-char proc_ipv6_forwarding[] = "/proc/sys/net/ipv6/conf/all/forwarding";
+static const char proc_ipv6_forwarding[] =
+	"/proc/sys/net/ipv6/conf/all/forwarding";
 
 int ipforward_ipv6(void)
 {
diff --git a/zebra/main.c b/zebra/main.c
index 838ad1cdf..731c4e161 100644
--- a/zebra/main.c
+++ b/zebra/main.c
@@ -84,7 +84,7 @@ uint32_t nl_rcvbufsize = 4194304;
 
 #define OPTION_V6_RR_SEMANTICS 2000
 /* Command line options. */
-struct option longopts[] = {
+const struct option longopts[] = {
 	{"batch", no_argument, NULL, 'b'},
 	{"allow_delete", no_argument, NULL, 'a'},
 	{"keep_kernel", no_argument, NULL, 'k'},
diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index c9a9a81b1..5e328b827 100644
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -83,8 +83,8 @@ struct gw_family_t {
 	union g_addr gate;
 };
 
-char ipv4_ll_buf[16] = "169.254.0.1";
-struct in_addr ipv4_ll;
+static const char ipv4_ll_buf[16] = "169.254.0.1";
+static struct in_addr ipv4_ll;
 
 /*
  * The ipv4_ll data structure is used for all 5549
diff --git a/zebra/rtadv.c b/zebra/rtadv.c
index f51c199f6..0adf654aa 100644
--- a/zebra/rtadv.c
+++ b/zebra/rtadv.c
@@ -72,7 +72,9 @@ DEFINE_MTYPE_STATIC(ZEBRA, RTADV_DNSSL, "Router Advertisement DNSSL")
 
 /* Order is intentional.  Matches RFC4191.  This array is also used for
    command matching, so only modify with care. */
-const char *rtadv_pref_strs[] = {"medium", "high", "INVALID", "low", 0};
+static const char *const rtadv_pref_strs[] = {
+	"medium", "high", "INVALID", "low", 0
+};
 
 enum rtadv_event {
 	RTADV_START,
diff --git a/zebra/rtadv.h b/zebra/rtadv.h
index f9bd2b1d3..409959d08 100644
--- a/zebra/rtadv.h
+++ b/zebra/rtadv.h
@@ -131,8 +131,6 @@ struct nd_opt_dnssl { /* DNS search list option [RFC8106 5.2] */
 } __attribute__((__packed__));
 #endif
 
-extern const char *rtadv_pref_strs[];
-
 #endif /* HAVE_RTADV */
 
 typedef enum {
diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
index e809d2ad3..86f41e807 100644
--- a/zebra/zapi_msg.c
+++ b/zebra/zapi_msg.c
@@ -1022,7 +1022,7 @@ static int zsend_table_manager_connect_response(struct zserv *client,
 
 /* Inbound message handling ------------------------------------------------ */
 
-int cmd2type[] = {
+const int cmd2type[] = {
 	[ZEBRA_NEXTHOP_REGISTER] = RNH_NEXTHOP_TYPE,
 	[ZEBRA_NEXTHOP_UNREGISTER] = RNH_NEXTHOP_TYPE,
 	[ZEBRA_IMPORT_ROUTE_REGISTER] = RNH_IMPORT_CHECK_TYPE,
@@ -2485,7 +2485,7 @@ stream_failure:
 	return;
 }
 
-void (*zserv_handlers[])(ZAPI_HANDLER_ARGS) = {
+void (*const zserv_handlers[])(ZAPI_HANDLER_ARGS) = {
 	[ZEBRA_ROUTER_ID_ADD] = zread_router_id_add,
 	[ZEBRA_ROUTER_ID_DELETE] = zread_router_id_delete,
 	[ZEBRA_INTERFACE_ADD] = zread_interface_add,
diff --git a/zebra/zebra_rib.c b/zebra/zebra_rib.c
index 781963793..605311769 100644
--- a/zebra/zebra_rib.c
+++ b/zebra/zebra_rib.c
@@ -3639,7 +3639,7 @@ struct route_table *rib_tables_iter_next(rib_tables_iter_t *iter)
 	 * Array that helps us go over all AFI/SAFI combinations via one
 	 * index.
 	 */
-	static struct {
+	static const struct {
 		afi_t afi;
 		safi_t safi;
 	} afi_safis[] = {